High CO at High RPM

This condition indicates abnormally high Carbon Monoxide with low or normal Hydrocarbons during cruise (2500 rpm).


POSSIBLE CAUSE ACTION


Faulty canister purge system Check Evaporative System.



[1][2]PCV malfunction Check PCV system. Testing and Inspection



Restricted exhaust Check for plugged exhaust system. Catalytic Converter



Incorrect Spark Advance Check Spark Controls (EST, ESC, etc...).



Fuel metering malfunction Check fuel pressure.
Perform injector balance test. Refer to FUEL SUPPLY AND AIR INDUCTION/DIAGNOSIS, TESTING AND INSPECTION PROCEDURES/TESTING PROCEDURES/FUEL INJECTOR BALANCE TEST.



Incorrect fuel pressure Inspect regulator operation